This invention relates to an iron golf club, and, more particularly, to an iron golf club having improved ball control.
In the game of golf, a golf club is swung by the golfer to impact a golf ball. The golf club has a head which impacts the golf ball, and a shaft that is grasped and swung by the golfer. There are three basic types of clubs, divided primarily according to the type of head and circumstances of hitting the golf ball: wood clubs to hit the golf ball long distances from an elevated tee; irons to hit the golf ball shorter, more controlled distances with controlled elevations; and putters to hit the golf ball for a short distance along the ground with a high degree of control. The present invention relates to irons, and does not relate to wood clubs or putters. (The term "iron" is a term of art referring to the design of the club, and does not refer to the material of construction.)
The golfer usually has a set of irons which vary according to the loft angle of the face of the golf club relative to the shaft, with increasing designation numbers being associated with increasing loft angles. The selection of the iron to be used depends upon the distance that the golf ball is to be hit and the degree to which the golfer desires back spin on the ball to halt forward roll. In each case, however, the golf ball lies on the ground and the golf club is swung with a high velocity so that the club head impacts the ball with high force. This use of the iron golf club distinguishes the use of the wood club, where the golf ball is usually hit from an elevated tee so that there is less contact of the underside of the club head with the ground, and the putter, where the velocity of the swing is relatively small.
A front face of the iron golf club head impacts the golf ball lying on the ground either squarely or slightly under the golf ball to project the golf ball on an upward trajectory. The bottom side of the iron club head, which is slightly convexly curved, either grazes the surface of the ground, which may be grass, turf, sand, preexisting divots, or the like, or actually digs into the ground slightly when the golf ball is struck.
The passage of the bottom side of the club head across the surface of the ground typically creates a substantial amount of retarding force on the club head, due to either or both of two reasons. First, the ground itself may have a texture, such as relatively high grass, that generates friction with the passage of the bottom side of the club head. Second, the highly skilled golfer, such as the professional, can usually control with great precision the vertical location of the club head and thence the degree of contact with the ground. The less-skilled golfer, on the other hand, has somewhat less control and may cause the bottom side of the club head to contact the ground with greater force than desired.
The retarding force generated between the bottom side of the swung iron and the ground affects the flight of the golf ball in two ways. First, it reduces the velocity of the club head and thence the force transmitted to the golf ball. The result is a shorter flight distance. Second, if the force is not symmetric, it can cause the club head to rotate slightly at the time of impact, with the result that the ball is hit in a direction slightly different from that desired. Both of these results are undesirable. Additionally, it is important to control the flight path of the ball responsive to the problem presented to the golfer.
The ground effects on golf club iron hitting performance are reduced with increasing skill of the golfer. However, for all golfers, there is a need for an iron club which, by the design of the club head, reduces the likelihood of adverse ground effects on hitting performance and also optimizes the hitting performance of the club. The present invention fulfills this need, and further provides related advantages.